Rotary pump with oblique rotor



Oct. 30, 1962 e. NEIDL ROTARY PUMP WITH OBLIQUE ROTOR 7 Sheets-Sheet 1 Filed Jan. 26, 1959 Fig. 5

INVEN TOR Oct. 30, 1962 G. NEIDL ROTARY PUMP WITH OBLIQUE ROTOR 7 Sheets-Sheet 2 Filed Jan. 26, 1959 INVENTOR Oct. 30, 1962 G. NEIDL ROTARY PUMP WITH OBLIQUE ROTOR 7 Sheets-Sheet 3 Filed Jan. 26, 1959 Fig. 15

Fig. 14 s"' "j/ 1f mvsurol? Oct. 30, 1962 G. NEIDL 3,060,862

ROTARY PUMP WITH OBLIQUE ROTOR Filed Jan. 26, 1959 7 Sheets-Sheet 4 IN VE N TOR GJYeatL Oct. 30, 1962 G. NEIDL 3,060,862

ROTARY PUMP WITH OBLIQUE ROTOR Filed Jan. 26, 1959 7 Sheets-Sheet 5 Pi 17 Ell 9 62 59 Fig. I9

Oct. 30, 1962 G. NEIDL ROTARY PUMP wrm OBLIQUE ROTOR '7 Sheets-Sheet 6 Filed Jan. 26, 1959 Fig.22

Fig. 23

Fig.25

INVEN TOR Oct. 30, 1962 NEIDL I 3,060,862

ROTARY PUMP WITH OBLIQUE ROTOR 7 Sheets-Sheet '7 Filed Jan. 26, 1959 3,06tL862 ROTARY PUMP WITH ()BLIQUE ROTOR Georg Neidl, Uferstrasse 6, Berlin 21), Germany Filed Jan. 26, 1959, Ser. No. 789,111 Claims priority, application Germany May 30, 1958 2 Claims. (Cl. 193103) The invention is in respect of a further development of the subject of application No. 637,230 now matured into Patent No. 2,956,503. In [the main patent, a rotary pump is described, the impeller of which, inter alia, is designed as an elliptical or circular disc which is mounted obliquely to the pump axis.

According to the present invention, where the impeller is constructed as a disc, the latter has to be secured obliquely on the pump shaft in such a way that, when the impeller is rotating, the edges of the impeller discs working surface facing towards the suction intake describe a circle, the diameter of which corresponds to the mouth of .the intake pipe where it connects with the pump housing. When actually making the disc-shaped impeller, it is possible to take a circular disc to start with and remove from same, at diametrically opposite points, crescent-shaped segments.

In order to promote a better suction in the material which is to be moved, it is a good thing, particularly when the material is viscous, to select the pump intake so large that its internal diameter corresponds substantially to the internal diameter of the pump housing. It is possible, by cutting out the intake pipe altogether, to connect the pump housing, on the latters intake side, directly on to a correspondingly large opening in the wall of the tank on which it is to be used.

It is further possible to shorten the pump housing in an axial direction in such a manner that the pump impeller projects partially out of the housing. Where this is the case, it is advisable for the housing to be mounted in such a Way that the pump shaft runs vertically. This arrangement has proved itself to be successful especially for shifting prepared mortar or cement, no matter whether the latter be in a container, cement pit, or a trough, or whether it be a question of conveying away, in the manner of a suction dredger operating in waterways, wet sand from the bottom of the water. By means of that part of the rotary pump which projects from the housing the water in the immediate vicinity of the pump impeller is whirled up violently and so the wet sand, mixed with the water, is drawn in through the rotary pump and passed on into the pressure outlet. This pump simultaneously performs, to a certain extent, the function of the pressurecumsuction pump in a customary suction dredger. For the purpose of increasing the output it is possible to provide, at diametrically opposite points in the pump housing, pressure outlets which, by means of appropriate bent pipings, are directed upward and united into a common pressure outlet in the region of the pump shaft.

With pumps whose disc-shaped impellers project partly from the housing, it is of advantage, at the open, front end of the pump housing starting from the housings cylindrical circumference, to fit, as permanent fixtures, guide rings or guide profiles preferably in the form of a truncated cone, which are executed as one-piece surfaces or divided up into sections. The pump discs can be convex, concave, or bent over in two directions. It is also possible to fit, on the circumference of the disc shaped pump impeller, an annular shoe surface which is preferably given a shape like that of a section of cylindrical casing in such a way that the shoe-rings outer surface lies parallel to the pump housings inner casing.

If, on the circumference of the disc-shaped pump impeller, teeth, prongs, or projections are provided which engage in correspondingly shaped grooves on the pump ififififil Patented Get. 36, 1962 housings inner circumference, then it will be found better for these grooves to be provided not directly on the circumference of the pump housing itself but in a special bushing which is pushed into the pump housing. According to the invention, it is an eminently practical measure, for reasons of simplified assembly, to design the bushinglooked at in an axial direction-in several parts, the advantage of this being that the grooved bushing can be fitted and removed without there being any necessity, at the same time, to remove the pump impeller from its overhung bearings. It may be found appropriate, at one point, especially in the region approaching the opening to the pressure outlet, to keep the housings walling free of any bushing segment. Now, in order to keep the remaining bushing segments inside the housing, there is inserted, in the region approaching the opening to the pressure outlet, a ring segment whose purpose is to maintain the clearance at the front end of the pump housing between the free-laying edges of the bushing segments.

For the purpose of increasing the crushing effect it may be of advantage, apart from the circumferential grooves running in a peripheral direction on the pump housing, to fit additional grooves or slots which cross the circumferential grooves or which run spirally, these grooves being variously profiled, presenting, more especially, triangular profiles.

In order to render uniform the crushing action occurring inside the pump during the actual pumping, it is of advantage to fit in the large opening in the pump housings cylinder Walling leading to the pressure outlet, an insert having holes arranged over its surface, this insent being not only curved according to the inner curvature of the housing, but in addition, having circumferential grooves in the same manner as the remainder of the pump housings inner surfaces. This ensures that the pump impellers prongs and teeth which continuously brush past the insert, clear away any foreign bodies from the holes in the insert, until such time as these foreign bodies have been broken up to the extent that they are able to pass through the holes in the insert and make their way on to the pressure outlet. Instead of these holes, there can be provided in the pump housings insert, towards the pressure outlet, slits lying parallel to each other and of a width and spacing-apart from each other such as match the breaking-up action desired. This slitted insert is especially suitable as a chopping mechanism in the beet industry.

For the purpose of further adaptation to the desired dimensions of the material which has to be chopped up, the outer diameter of the rotary member can be matched to the pump housings inner diameter, the clearance between the pump impellers outermost circumference and the pump housings inner circumference being matched to the size of the slits to be made.

It may be appropriate to widen the slitted insert considerably towards the bottom, the inlet opening into the pressure outlet also being widened by bellying out the housings walling at this point. It is also possible for cutters to be fitted into the slits in such a way that the cutter blades project somewhat beyond the inner circurnference of the insert or inner circumference of the pump housing, into the interior of the housing, though, obviously, the diameter of the pump impeller will then have to be smaller than the pump housings inner diameter. The cutters can also be constructed as double knives.

With a view to enabling the rotary pump to be used in the chemical industry, particularly for the job of shifting viscous substances such as, more especially, artificial silk spinning solutions, it is appropriate to connect both the suction intake as Well as the pressure outlet, in the i the pressure outlet axes coinciding with each other.

Finally, it is possible to construct the pump impeller in such a way that those points or lines or surfaces of the pump impeller which rotate concentrically to the inner walls of the housing, are vaulted to the rear in the marginal regions contrary to the shafts direction of rotation. The effect of this is to prevent, to a large extent, the eddyings which would otherwise occur in the liquid being pumped inside the pump housing by reason of the sharp edges of the impeller, and the pumps efficiency is thus appreciably increased.

The curvatures in the pump impellers marginal zones are produced by transmitting to the pump impeller itself or a model of same, on a machine tool, rotary motions corresponding to the actual pump operation, a forming or pressing tool being shoved forward step by step, slide fashion, vertically to the machines direction of rotation. The tool is clamped'in a holder and it is moved along those longitudinal lines past the pump impeller, which correspond to the longitudinal lines of the housing, these longitudinal lines being so fixed that, after the pump impeller has been finished, when it rotates in its own housing as against this housing, concentric play remains or the pump impeller runs in the housing free of play. It is also possible, after the pump impeller has been given its edge curvature, to cut grooves into the curvatures using a profiled cutting tool, the profiled tool being advanced intermittently during the turning operation on the lathe. Corresponding grooves may' also be provided on the inner surface of the housing, into which the prominences on the pump impellers circumference engage.

The invention will now be further described with reference to the accompanying drawings in which:

FIGURE 1 is an axial section through a rotary pump in which the disc-shaped pump impeller has been produced from a circular disc by cutting off crescent-shaped segments, f

FIGURE 2 is a plan view of the pump disc in accordance with the invention, in the direction of the arrow B of FIGURE 1,

front ends,

FIGURE 8 is a cross section, through the equipment corresponding to the line VIIIVIII of FIGURE 7,

FIGURE'9 is a pump similar to that 'as shown in FIGURE 7, in which the pump shaft is mounted in the a side wallings of a tank inside which the pump is fitted, FIGURE 10 is an axial section through a pump in which there is a guide ring fitted on the open end of the housing, 7 7

FIGURE 11 is a ,form of execution similar to that shown in FIGURE 10, in which however, the" pump, disc is executed in an elliptical shape, 7 1

FIGURE 12 is a side elevation view of the pump as represented in FIGUREll, in the direction of the arrow U, and in which the pump disc is'represented in dot-anddash lines, 7 I 1 FIGURES 13 is an axial section through a pump with concavely curved pump disc,

FIGURE 14 is an axial section through a pump hav- 7 a ing' a pump-impeller disc, the cross section of which is 4 FIGURE 16 is a front-end view of a rotary pump in which two segments of the housings bushing have been fitted into place,

FIGURE 17 is an axial section through a rotary pump with circumferential grooves and longitudinal slots,

FIGURE 18 is a cross section through the pump in accordance with the line XVIIIt-XVIII of FIGURE 17, FIGURE 19 is a plan view of a perforated insert for the pump housing as per FIGURE 17,

FIGURE 20 is a cross' section similar to that of FIG- URE 18 through a pump'with perforated insert fitted,

FIGURE 21 is a partially enlarged axial section through the pump at the point where the perforated insert is fitted, corresponding to the line XX-I-JQH of FIGURE 19, a

FIGURE 22 is a radial section through a rotary pump with enlarged opening to the pressure outlet,

FIGURE 23 is an insert fitted with slits, for the opening giving access to the pressure outlet, corresponding to the form of execution of FIGURE 20,

FIGURE 24 is a radial section through arotary pump with suction intake and pressure outlet arranged in the bottom part of the housing, 7

FIGURE 25 is an axial section through the pump along the line XXV-XXV of FIGURE 24,

FIGURE 26 is a side view of a disc-shaped pump impeller fitted on a shaft,

FIGURE 27 is a plan view of the component as shown in FIGURE 26, in the direction of the arrow C,

FIGURE 28 'is a cross' section through the pumpimpeller disc corresponding to the line XXVIIIXXVIII of FIGURE 27, after diametrically opposite edge portions have been curved over,

FIGURE 29 is an axial section through a pump housing fitted with a pump impeller designed in accordance I with FIGURE 28,

FIGURE 30is a mean cross section through a pump impeller into which teeth have been worked,

FIGURE 31 is a mean cross section through a pump impeller inwhich the undercuts of the curvatures duly produced have been filled in with material, and

FIGURE 32 is a ground plan of a pumping installation with three pumps connected up one behind the other. a

In FIGURES 1 and 2 issketched in, in dot-and-dash lines, a rotary pump such as is the subject of the older patent, the pump impeller '2 being of a circular shaped construction in' the direction of-the projection B. The pump disc 3 of the present inyention is provided with front and rear faces 3a and 3b, r'espectively, and rear face 3b is mounted on shaft 1 obliquely to the longitudinal axis of the shaft. jThe disc 3 is produced by cutting off or removing crescent-shaped segments 2a of the circular impeller 2, as is clearly apparent in FIGURE 2'. These removed crescent-shaped segments are located at'diametrically opposite points and provide edges located closer to the axis of the shaft l-than the edges which correspond to the full diameter of the circular disc. The closer edges are located at a distance from the axis of the shaft 1 which is smaller than one-half of the diameter of'the disc 2. e

In a corresponding'fashion, housing '1 of the present invention is provided by narrowingsuch housing from that identified by the broken lines 4 in FIGURE 1.

Whenshaft I is rotated, it is apparent that disc 3 will likewise be rotated and edge K of the front face of the disc facing suction intake 5 will describe a circle corresponding to the innner diameter of the intake or' inlet 5. By virtue of this particular arrangement, there is eliminated a dead space, so that the materialentering the inlet 5 in the direction of the arrow A impinges directly on the front; face 3a of the disc lifThis eliminates eddy- Iing, and the materialis gently guided upwards along the front face of the disc to pressure outlet pipe, as indicated by dotted lines B. V V r Furthermore, it will be noted that the peripheral edge of the disc 3 directed towards the inlet 5 is angled towards the axis of the shaft 1, so that the edge rotates approximately over the circle formed by the inner diameter of the inlet 5.

By way of contrast, FIGURE 3 shows a rotary pump in which the edge K facing the suction intake describes, when it rotates, a circle which is larger than the transverse cross section of the suction intake 5. The effect of this is that eddying occurs between the edge K in its lowermost position and the suction pipe cover, when the liquid is being drawn in.

According to the form of execution as shown in FIG- UR-E 4, there is no cover-plate fitted on the suction end of the housing 5 but instead, a piece of piping 2' the diameter 3' of which corresponds to the diameter 4' of the pump housing 1. Since this pump does not consequently present on its suction end, any narrowing due to the presence of a suction-intake pipe, the pump impeller need not have the special shape which has been referred to in connection with FIGURES 1 and 2 since there are no dead spaces along the pump impellers lower edge and, consequently, no eddyings are set up either. Connected on to the piece of piping 2 there can be a pipe elbow 5', the diameter 6' of which corresponds to the diameter 3 of the piece of piping 2'. By constructing the .pump in this fashion, a perfect pumping action is obtained even when shifting viscous substances.

It is possible, in accordance with FIGURE 5, to join the pump housing 10' by its flange 11 direct to the wall of a tank 13' so that the liquid in the tank 13' is conveyed direct through the pump housing by means of the pump impeller 15 into the pressure outlet 14'. While the liquid is being drawn in, there is set up, inside the tank 13, a conical eddy 18'. In order, particularly when moving liquids with fibrous materials in them, to prevent any deleterious matting together or streamer formation as it is called, it is a useful practice to fit a partition wall 19' in the tank in such a way that this partition wall passes through the centre axis of the liquids cone-shaped eddy 18.

In the form of execution as represented in FIGURE 6 the rotary pump 29 is suspended in a tank 21 from above in such a way that the pump shaft 22 hangs vertically. In addition, the housing 23 of this pump is shortened in an axial direction in such a way that the pump disc 24 projects downwards out of the front end 25 of the pump housing. The drive motor 26 is constructed as a waterproof sealed underwater motor 50 that the complete pump unit can be lowered into a shaft in the manner of a drainage pump. It is a useful measure, for reasons of improved efficiency and spread of the weight load, to provide on diametrically opposite portions of the pump housings walling, one pressure outlet 27 each which, via a pipe elbow 28 in each case, directs the liquid which has been drawn in, to a common pressure outlet 29 arranged coaxially to the shaft 22. In order to suction sand or like substance away, the pump is lowered so that the impeller, which projects from the pump housing, stirs up the sand as it rotates quickly, and mixing the sand with the water located above same, draws in the mixture and passes it along to the pressure outlet 2%.

In the form of execution as shown in FIGURES 7 and 8, not only is the left-hand cover plate omitted but also the right-hand cover plate 8' (cf. FIGURE 4) and substituted by a cover plate with ribs 3-1 carrying the bearing 32. for the shaft 9'. The ribbed cover plate is flange-fitted to the housing 1'. When such a pump as this is placed in a tank 33 out of which the shaft 9' passes, via a stufling box 34, to the motor-not depicted-then the pump will deliver via its pressure outlet 35, drawing in the material from the tank 33 from the left and right hand sides simultaneously.

According to the form of execution as shown in FIG- URE the pump shaft 9', being a double-mounted shaft, is carried in bearings 37 and 38 in the wallings of the tank 36. This form of execution may be concerned With nothing more than an ordinary mixing tank if the pressure outlet 35, as shown in dotted, arrow-headed lines, is so constructed that it branches off fork-wise so that the liquid is continuously directed back into the tank.

In the form of execution as depicted in FIGURE 10, the pump impeller also projects partially outside the pump housing, the mid-point M of the pump disc R, which serves simultaneously as the point at which the disc is fastened to the pump shaft, being advanced towards the open end 41 of the pump housing by a certain distance 46, as against the mid-point M of the housing 1'.

In order not to discontinue the pump housing 1 unduly abruptly as against the tank, and to prevent any chopping during the suction action, guide rings or guide profiles running the whole way round, or split up between themselves over the circumference, are provided for fitting, as stationary fixtures, on the open end of the pump housing.

According to the form of execution which is depicted in FIGURES 11 and 12, the pump disc is designed as an ellipse. Its point of attachment M to the shaft 1 is shifted, as against the housings mid-point M, towards the intake end. It is appropriate for the elliptical arcs E to be cut ofi along a chord S running parallel to the cover plate A of the pump housing 1, and to provide for the pump disc to be mounted inside the housing in such a Way that the edge S rotates with little or no clearance as against the cover plate A of the pump housing. In FIGURE 11, represented in dotted lines, is an elevation on the pump disc in the direction of the arrow Q. In a modified arrangement of this form of execution, the housing-as drawn in dot-and-dash lines in FIGURE 1l-may be extended up to the front edge T so that, in this instance, the pump disc does not project outside the pump housing.

If the pump disc is executed in such a manner that the elliptical arcs E plotted in dotted lines in FIGURE 11 become arcs of a circle or show an arc shape corresponding to the form of execution as per FIGURES l and 2 which is obtained by cutting off crescent shaped portions at two diametrically opposite places, then the gaps between the individual points in the arcs E and the portions of the housing ls walling pertaining to same will be of differing size.

According to the form of execution as shown in FIG- URE 13, the pump disc R is executed in a curved shape in the axial section in such a Way that it appears convex as against the pump shaft 1. In the form of execution as per FIGURE 14, a pump disc 43 is provided for which is executed in a curved shape bent over in two directions and thus, in axial section, it has the appearance of a question mark. The pump discs edge 4-6 facing the cover plate 44 of the suction intake 45 is cut off along a chord S as can be seen in the dot-and-dash representation above the pump housing. It is also possible to cut off the pump disc according to another form of executionplotted in dotted lines in FIGURE l4- along a chord S lying opposite the chord S. In fact, various forms of execution are possible, involving segments either on only the one or only the other side, or on both sides, along chords taken to the pump disc.

According to the form of execution as depicted in FIGURE 15, there is fitted permanently on the circumference of a disc-shaped pump impeller 47 a shoe surface 49 rotating axially with the shaft axis 48, which is formed from a ring-shaped flat iron which one may imagine as having been cut from a cylinder, in that two parallel surfaces of out are arranged running not only parallel to each other but also parallel to the surface of the V Y pump disc. The effect of this is that this shoe-ring rotates around the inner circumference of the pump housing 1 practically without'clearance thereby ensuring a particularly good seal on'accou'nt of its width.

In the form of execution as given in FIGURE 16, there is pushed into the pump housing 1' a bushing consisting of three parts 59, 51, and 52. The fitting of this multi-piece bushing into the housing is effected by turning the pump disc 53 in such a way that one of the bushing segments is pushed so far into the housing until the flange on this segment lies flush against the front end of the housing 1'. Then, the pump disc 53 is turned round to the right by about 90 so that its teeth 55 on one side engage in the grooves in the pushed-in bushing segment 50. Then the second segment 51 is pushed into the housing 1' and the pump disc is'turned further so that the teeth of the pump disc engage in the grooves of this second segment 51. Nextfthe third segment 52 is pushed into the housing. Finally, a ring-shaped segment 56 is inserted in the recess 54, thus ensuring that the individual bushing segments 50, 51, and 52 are firmly secured in their places.

According to the form of execution as depicted in FIGURES 17 and 18, the disc-shaped pump impeller 57 has, on its circumference, teeth 58 which engage in circumferential grooves 59 along the inner circumference of the pumps housing. Transversely to these circumferential grooves 59 the inner circumference of the pump housing has lengthwise slots 60 running parallel to 'the housings axis, of triangular, or other shaped profile, which cross with the circumferential grooves 59.

It is a useful practice, in accordance withthe' form of execution as shown in FIGURES 17 to 21, to insert in the opening 61 of the pump housing '1" which leads to the pressure outlet 62,21 perforated insert 63 provided with holes 64 evenly distributed over its surface. The perforated insert 63, acting as a strainer, is curved corresponding to the curvature of the inner. circumference of the pump housing 1' and equipped on its inner surface with slots 65 which correspond to the circumferential grooves 59 of the pump housing 1'. It is of advantage to provide holes 64 in the bottom of these slots 65. The

.holes may be circular, elliptical, rectangular, or of any other shape. The periphery of the holes can be of wavy, spiral, screw-threaded, roughened, or barbed contour.

The object of fitting the perforated insert 63 is'that all foreign bodies such as lumps and conglomerates entering the pump housing 1 through thesuction intake 66 are no longer able to proceed straight away into the pressure outlet 62, but must, first of all, pass through the holes 64 of the perforated insert 63. However, they cannot do this until they have been sufficiently broken or crum bled up by the pump impeller 57 to enable them to pass through the holes 64 of the perforated insert 63.

For the purpose of increasing the pumping output and the slicing effect, the slitted insert 67 is substantially Wid ened towards the bottom, as FIGURE 22 shows, the in let opening 68 into the pressure-outlets pipe 69 being widened also at the same time by an appropriate bellyingout 79 of the housings walling'7'1 at this point. The effect of this is to stop the squeezing often observed during the slicing operation. Into the slits 67 it is possible, as FIGURE 22 shows, to fit cutters 72 which are bent over, eagle-beak fashion, contrary to the pump i-mpellers 7 direction of rotation, and thereby increase the slicing action. Where this ;is the case, the. outer diameter of the pump impellerhas to be selected correspondingly smaller,

a According to the form of execution of the FIGURES 24 and 25, both the suction-intake pipe 75.as well as the pressure outlet pipe 76 are connectedfup tangentially to the pump housing 1 in the latters bottom portion in such a Way that the lowermost, inner generatrix 77 or 78 as the case may be, connects tangentially with the inner superficies 79. In this manner, viscous substances can be shifted particularly Well. 7

According to the form of. execution as represented in FIGURES 26 to 29, an elliptical disc 80 is taken as a basic component, which is securely attached to the shaft 81. The shaft is clamped in a three-jaw chuck 82 of a lathe, and a profiled iron 83 is clamped in the tool rest, the former being moved back and forth, in the direction of the double-arrow 84, over the rotating disc 80. The profiled iron is first of all moved back and forth along the disc at some distance from the small axis 85 and then pushed forward graduallyin the direction of the arrow 86 by means of the tool rest. The result of all this is that the two diametrically opposite edges which are in the immediate vicinity of the profiled iron 83, are gradually bent over to the rear, the profiled iron being fed forward only as far as the radius 87. In this manner, the lines of demarcation 88, 89 are produced. The edges of bend 9t 91 are clearly visible in FIGURE 28, and, in FIGURE 29 the pump impeller can be seen fitted in a corresponding pump-housing with a radius 87 approximately. This figure only shows the one edge of bend 99. It can also be seen that the pump impeller rotates in the housing with a clearance S, and this over the entire length of the pump housing. 7

If the pump impeller is intended to be madeof a thickwalled disc, the edges of bend will first of all be produced on a full-size model made, of some soft, easily workable, modelling material such asrlead forexample, and the model is then duly used as a master pattern'for the production models, Whether it is first cast in plaster and then subsequently made in some other material, or whether wooden patterns are made from this model and then, subsequently, castings are made thereof; FIGURE 30 represents a cross section through the pump .disc corresponding to FIGURE 28, the connection to the pump shaft being imagined as being not present. In this pump disc, grooves or slots 92 have been cut into the bent-over edges 99, 91, by means of a cutting or lathe tool. The prominences thus produced between the grooves are made to fit into corresponding circumferential grooves in the housings inner walling when the impeller is fitted into the housing. 7 V V According to the form of execution as shown in FIG- URE 31, the bent edges 90, 91 are undercut at point 93, that is to say, they are hollow. Now, in order to prevent pumped material from accumulating in the undercuts 93, the latter are filled in with some filler material.

The form of execution of the pump shown in FIG- URES 16 to.22 has proved its worth in the paper industry particularly and it is suitable as a substitute for the edge mills generally employed there for breaking up pieces of wood, f0I', not only is a saving effected in the cost of purchasing these expensive edge i'nillsQbut, in addition, there is a considerable saving in the time taken to reduce the wood pieces down to'wood-fib re pulp, because the reduction takes place in a fraction of the time normally required using edge mills.

Such machines as per the invention are suitable for the disintegration and/or pumping of materials which have to be moved and which are not capable of How movement in themselves. Once these materials have been brought into the machine however, they are e processed by, the latter. Thus, it requires but little imagination to picture the machine as per FIGURES 4 and 5,

or 10 and 11 for instance, as being turned over clockwise by when the pump shaft will then point downwards and the pump impeller will be driven from underneath. A funnel is placed vertically on the inlet feeding into the housing, so that the material being dealt with drops down under its own gravity on to the rotating pump impeller and is then processed by the latter.

Designing the pump as per the invention with a pump shaft thus arranged vertically is of particular advantage everywhere where commodities have to be shifted which, in their final stage have to be in a disintegrated form, such as is the case for example with fish for making into fish meal, sugar beet, and the like. These commodities which, in their initial stage are not capable of flowing along by themselves and which therefore are incapable of being suctioned into a pump, will drop into the pumpfitted vertically-under their own Weight and, after having een broken up inside the pump, will be converted to a pulpy mass having a high moisture content, so that they are then able to be transmitted through the pressure line on to the place at which they are further processed.

According to the form of execution as shown in FIG- URE 32, it may be found appropriate, Where toothed impellers are in use, to connect up in series, two or more pumps 94, 95, 96, the consecutive pump discs being constructed with reducing sizes of teeth in such a way that the first pump 94 has the largest teeth and the last pum 96 has the smallest.

All the pumps can be equipped with an infinitely variable gear so as to enable the pump speed necessary in any particular case to be set accurately.

I claim:

1. A pump for the displacement of a sludge and viscous liquids comprising:

a housing having a pumping chamber therein, said chamber being provided with a front wall, a rear Wall and a peripheral wall, the inner surface of said peripheral wall conforming to a generally cylindrical surface of revolution about an axis, said front wall being provided with a centrally positioned circular intake, said peripheral wall being provided with a radial discharge port between said front and rear Walls;

a shaft extending axially into said chamber through said rear Wall; and

a generally disk-shaped impeller having a substantially flat surface facing said intake, said impeller being secured to said shaft with said flat surface in a plane inclined to said shaft, said fiat surface being bounded by a substantially elliptical periphery, one axis of said inclined flat surface on rotation of said impeller about said shaftdefining a circlie substantially equal to the area of said intake, the other axis of 10 said inclined flat surface being substantially equal to the diameter of said surface of revolution.

2. A pump for the displacement of sludge and viscous liquids comprising:

a housing having a pumping chamber therein, said chamber being provided with a front Wall, a rear wall and a peripheral wall, the inner surface of said peripheral wall conforming to a generally cylindrical surface of revolution about an axis, said front wall being provided with a centrally positioned circular intake, said peripheral Wall being provided with a radial discharge port between said front and rear walls;

a shaft extending axially into said chamber through said rear wall; and

a generally disk-shaped impeller having a substantially flat surface facing said intake, said impeller being secured to said shaft, said flat surface being bounded by a substantially elliptical periphery, the minor axis of said inclined flat surface including an acute angle with said shaft and, on rotation of said impeller about said shaft, defining a circle substantially equal to the area of said intake, the major axis of said inclined flat surface extending at right angles to said shaft and being substantially equal to the diameter of said surface of revolution.

References Cited in the file of this patent UNITED STATES PATENTS Re. 1,380 Kingsland Ian. 6, 1863 2,225,171 Hammes Dec. 17, 1940 2,336,798 Nash Dec. 14, 1943 2,343,714 Swenson Mar. 7, 1944 2,362,922 Palm Nov. 14, 1944 2,501,275 Heller Mar. 21, 1950 2,775,348 Williams Dec. 25, 1956 2,956,503 Neidl Oct. 18, 1960 FOREIGN PATENTS 27,180 Finland Feb. 15, 1955 132,679 Great Britain Sept. 25, 1919 183,980 Austria July 15, 1951 205,680 Australia Jan. 16, 1957 932,556 Germany Sept. 5, 1955 OTHER REFERENCES Hoelscher: Inclined Rotor Pumps, 4 pages, February 11, 1958. 

